Electrical storage batteries, whether of the paste, gelled or liquid electrolyte type, have been in use for decades. And at least in the case of lead-acid batteries as used in motor vehicles, golf carts, wheel chairs, stand-by power supplies and the like, the batteries are often interconnected to one another. Such "ganging" of batteries (whether in series, in parallel or both) is to obtain higher voltage and/or higher current capability. For example, two 12 volt batteries connected in series provide 24 volts across the pair.
Very commonly, such batteries are ganged together using a cable which includes a length of stranded, "rope-like" wire with a metal connector (of the clamping or bolt-on type) at each end. When connecting batteries in series, such cable is used to attach the "positive" or "+" terminal of one battery to the "negative" or "-" terminal of the other.
The interconnecting cable must be sufficiently long, e.g., six to ten inches or more depending upon battery size, to effect easy interconnection. And for a given current-carrying capacity, the cross-sectional area of the stranded wire needs to be increased in longer cables. Such increase in area (and consequent increase in cost) maintains resistivity per unit length at an acceptable level.
Yet another fact impacting the cost and resistivity of conventional interconnection cables involves attachment of metal connectors to the stranded wire. Such attachment has adverse implications for labor and material cost and results in a wire-connector joint. In an arrangement involving conventional cable interconnecting two batteries, there are four joints, one each at the two battery terminals and one at each of the two junctions of the wire and the connectors. Each joint in a battery circuit presents another opportunity for corrosion and increased circuit resistance.
Often, the metal battery terminals to which connections are made are not insulated or are not fully insulated. The same may be said for the metal connectors at the ends of the connector cable. Therefore, in a ganged group of batteries providing relatively high voltage across the output terminals, the exposed metal parts (battery terminals, connectors and even short lengths of cable) can present a shock hazard. The risk of such hazard increases with increasing voltage. Battery arrays which produce 480 volts are not uncommon
And the battery connection "hardware" is not the only aspect of concern with batteries, whether ganged or otherwise. Installation and maintenance of the inter-battery connections requires tools and such tools, usually made of steel, are electrically conductive. These tools present a shock hazard and can cause sparks and arcing. This can ignite battery gasses (hydrogen and oxygen) and cause lethal explosions.
Yet another aspect of conventional batteries is that they are not easily stacked, i.e., vertically ganged. In some types of installations, vertical ganging makes better use of available space than horizontal ganging.
An improved battery connection apparatus which addresses and resolves shortcomings of conventional battery interconnection cables would be a significant advance in the art.